In a famous experiment, people asked to count basketball passes failed to notice a striking interloper in the game.

In a famous psychology experiment, participants watching a video of people passing a basketball around while moving missed a remarkable sight: Midway through the video, someone wearing a gorilla suit strolls through the exercise, pauses to beat his chest, and moves on. The key was that participants were asked to count the number of passes made by players wearing white shirts, and the focus on one activity induced a kind of blindness to the extraordinary visitor.

A new study shows that “inattentional deafness” exists, too. Forty-five people listened to a 3D, stereo recording, lasting just over a minute, of two men and two women independently discussing preparations for a party. Half the participants were instructed to listen closely to the men’s conversation, half to the women’s.

Halfway through the recording, a man moves through the audio landscape saying “I’m a gorilla. I’m a gorilla,” before exiting. This lasts 19 seconds. Afterward, when asked if they heard anything odd, 90% of the participants who were attending to the male voices mentioned the gorilla-man — but only 30% of the participants focusing on the female voices did….

Tim Wakefield, one of the most successful knuckleball pitchers in recent years.

I thought I knew, but this cool Washington Post graphic says I’m wrong: Knuckleballs don’t flutter — that they appear to may be the result of an optical illusion, says the neuroscientist Arthur Shapiro. They “stick to their trajectory nearly as closely as every other type of pitch.” It’s simply (or not-so-simply!) that this trajectory varies unpredictably from throw to throw.

Biographies

Gary Rosen is the editor of Review and the former managing editor of Commentary magazine. His articles and reviews have appeared in the Wall Street Journal, New York Times, Washington Post, and Los Angeles Times. He is the author of "American Compact: James Madison and the Problem of Founding" and the editor of "The Right War? The Conservative Debate on Iraq."